Refractory Technology MCQs

Question 1

Refractories are dried in the

Accepted Answer

Tunnel kilns

Answer

Rotary kilns

Answer

Sun

Answer

None of these

Question 2

Pick out the wrong statement.

Accepted Answer

Vitrification of fireclay material is done to increase its porosity

Answer

Fluxing material like lime is added in clay to reduce the vitrification temperature

Answer

Main constituents of clay are alumina and silica

Answer

Addition of sand in ceramic materials makes it non-plastic, increases its fusion point and reduces its shrinkage on burning

Question 3

Maximum apparent porosity of magnesite bricks is about __________ percent.

Accepted Answer

24

Answer

8

Answer

44

Answer

58

Question 4

With increase in the alumina content in firebricks, its fusion point (refractoriness)

Accepted Answer

Increases

Answer

Decreases linearly

Answer

Remains unchanged

Answer

Decreases

Question 5

Refractoriness under load (RUL) is the most important property for the refractory bricks

Accepted Answer

At the hearth bottom of the furnace on which stock is placed

Answer

Used for furnace insulation

Answer

Used in the roof of the furnace

Answer

None of these

Question 6

Spray test determines the __________ of refractories.

Accepted Answer

Resistance to slag penetration

Answer

Resistance to CO attack

Answer

RUL

Answer

Permanent linear change

Question 7

Fireclay bricks are not used in the

Accepted Answer

By-product coke oven walls

Answer

Beehive coke oven

Answer

Combustion chamber of B.F. stoves

Answer

Coke oven regenerators

Question 8

Chrome magnesite is not used in the

Accepted Answer

Wear out lining of steel melting furnaces

Answer

Inner lining of L.D. converter

Answer

Aluminium melting furnaces

Answer

All of the above

Question 9

Dolomite bricks have good resistance to attack by

Accepted Answer

Molten steel

Answer

Iron oxide

Answer

Lime slag

Answer

None of these